ouch/src/commands.rs
2021-11-25 11:57:47 +01:00

727 lines
33 KiB
Rust

//! Core of the crate, where the `compress_files` and `decompress_file` functions are implemented
//!
//! Also, where correctly call functions based on the detected `Command`.
use std::{
io::{self, BufReader, BufWriter, Read, Write},
ops::ControlFlow,
path::{Path, PathBuf},
};
use fs_err as fs;
use utils::colors;
use crate::{
archive,
error::FinalError,
extension::{
self,
CompressionFormat::{self, *},
Extension,
},
info,
list::{self, ListOptions},
progress::Progress,
utils::{
self, concatenate_os_str_list, dir_is_empty, nice_directory_display, to_utf, try_infer_extension,
user_wants_to_continue_decompressing,
},
warning, Opts, QuestionPolicy, Subcommand,
};
// Used in BufReader and BufWriter to perform less syscalls
const BUFFER_CAPACITY: usize = 1024 * 64;
fn represents_several_files(files: &[PathBuf]) -> bool {
let is_non_empty_dir = |path: &PathBuf| {
let is_non_empty = || !dir_is_empty(path);
path.is_dir().then(is_non_empty).unwrap_or_default()
};
files.iter().any(is_non_empty_dir) || files.len() > 1
}
/// Entrypoint of ouch, receives cli options and matches Subcommand to decide what to do
pub fn run(args: Opts, question_policy: QuestionPolicy) -> crate::Result<()> {
match args.cmd {
Subcommand::Compress { mut files, output: output_path } => {
// If the output_path file exists and is the same as some of the input files, warn the user and skip those inputs (in order to avoid compression recursion)
if output_path.exists() {
clean_input_files_if_needed(&mut files, &fs::canonicalize(&output_path)?);
}
// After cleaning, if there are no input files left, exit
if files.is_empty() {
return Err(FinalError::with_title("No files to compress").into());
}
// Formats from path extension, like "file.tar.gz.xz" -> vec![Tar, Gzip, Lzma]
let mut formats = extension::extensions_from_path(&output_path);
if formats.is_empty() {
let error = FinalError::with_title(format!("Cannot compress to '{}'.", to_utf(&output_path)))
.detail("You shall supply the compression format")
.hint("Try adding supported extensions (see --help):")
.hint(format!(" ouch compress <FILES>... {}.tar.gz", to_utf(&output_path)))
.hint(format!(" ouch compress <FILES>... {}.zip", to_utf(&output_path)))
.hint("")
.hint("Alternatively, you can overwrite this option by using the '--format' flag:")
.hint(format!(" ouch compress <FILES>... {} --format tar.gz", to_utf(&output_path)));
return Err(error.into());
}
if !formats.get(0).map(Extension::is_archive).unwrap_or(false) && represents_several_files(&files) {
// This piece of code creates a suggestion for compressing multiple files
// It says:
// Change from file.bz.xz
// To file.tar.bz.xz
let extensions_text: String = formats.iter().map(|format| format.to_string()).collect();
let output_path = to_utf(output_path);
// Breaks if Lzma is .lz or .lzma and not .xz
// Or if Bzip is .bz2 and not .bz
let extensions_start_position = output_path.rfind(&extensions_text).unwrap();
let pos = extensions_start_position;
let empty_range = pos..pos;
let mut suggested_output_path = output_path.clone();
suggested_output_path.replace_range(empty_range, ".tar");
let error = FinalError::with_title(format!("Cannot compress to '{}'.", to_utf(&output_path)))
.detail("You are trying to compress multiple files.")
.detail(format!("The compression format '{}' cannot receive multiple files.", &formats[0]))
.detail("The only supported formats that archive files into an archive are .tar and .zip.")
.hint(format!("Try inserting '.tar' or '.zip' before '{}'.", &formats[0]))
.hint(format!("From: {}", output_path))
.hint(format!("To: {}", suggested_output_path));
return Err(error.into());
}
if let Some(format) = formats.iter().skip(1).find(|format| format.is_archive()) {
let error = FinalError::with_title(format!("Cannot compress to '{}'.", to_utf(&output_path)))
.detail(format!("Found the format '{}' in an incorrect position.", format))
.detail(format!("'{}' can only be used at the start of the file extension.", format))
.hint(format!("If you wish to compress multiple files, start the extension with '{}'.", format))
.hint(format!("Otherwise, remove the last '{}' from '{}'.", format, to_utf(&output_path)));
return Err(error.into());
}
if output_path.exists() && !utils::user_wants_to_overwrite(&output_path, question_policy)? {
// User does not want to overwrite this file, skip and return without any errors
return Ok(());
}
let output_file = fs::File::create(&output_path)?;
if !represents_several_files(&files) {
// It's possible the file is already partially compressed so we don't want to compress it again
// `ouch compress file.tar.gz file.tar.gz.xz` should produce `file.tar.gz.xz` and not `file.tar.gz.tar.gz.xz`
let input_extensions = extension::extensions_from_path(&files[0]);
// We calculate the formats that are left if we filter out a sublist at the start of what we have that's the same as the input formats
let mut new_formats = Vec::with_capacity(formats.len());
for (inp_ext, out_ext) in input_extensions.iter().zip(&formats) {
if inp_ext.compression_formats == out_ext.compression_formats {
new_formats.push(out_ext.clone());
} else if inp_ext
.compression_formats
.iter()
.zip(out_ext.compression_formats.iter())
.all(|(inp, out)| inp == out)
{
let new_ext = Extension::new(
&out_ext.compression_formats[..inp_ext.compression_formats.len()],
&out_ext.display_text,
);
new_formats.push(new_ext);
break;
}
}
// If the input is a sublist at the start of `formats` then remove the extensions
// Note: If input_extensions is empty then it will make `formats` empty too, which we don't want
if !input_extensions.is_empty() && new_formats != formats {
// Safety:
// We checked above that input_extensions isn't empty, so files[0] has an extension.
//
// Path::extension says: "if there is no file_name, then there is no extension".
// Contrapositive statement: "if there is extension, then there is file_name".
info!(
accessible, // important information
"Partial compression detected. Compressing {} into {}",
to_utf(files[0].as_path().file_name().unwrap()),
to_utf(&output_path)
);
formats = new_formats;
}
}
let compress_result = compress_files(files, formats, output_file);
// If any error occurred, delete incomplete file
if compress_result.is_err() {
// Print an extra alert message pointing out that we left a possibly
// CORRUPTED FILE at `output_path`
if let Err(err) = fs::remove_file(&output_path) {
eprintln!("{red}FATAL ERROR:\n", red = *colors::RED);
eprintln!(" Please manually delete '{}'.", to_utf(&output_path));
eprintln!(" Compression failed and we could not delete '{}'.", to_utf(&output_path),);
eprintln!(" Error:{reset} {}{red}.{reset}\n", err, reset = *colors::RESET, red = *colors::RED);
}
} else {
// this is only printed once, so it doesn't result in much text. On the other hand,
// having a final status message is important especially in an accessibility context
// as screen readers may not read a commands exit code, making it hard to reason
// about whether the command succeeded without such a message
info!(accessible, "Successfully compressed '{}'.", to_utf(output_path));
}
compress_result?;
}
Subcommand::Decompress { files, output_dir } => {
let mut output_paths = vec![];
let mut formats = vec![];
for path in files.iter() {
let (file_output_path, file_formats) = extension::separate_known_extensions_from_name(path);
output_paths.push(file_output_path);
formats.push(file_formats);
}
if let ControlFlow::Break(_) = check_mime_type(&files, &mut formats, question_policy)? {
return Ok(());
}
let files_missing_format: Vec<PathBuf> = files
.iter()
.zip(&formats)
.filter(|(_, formats)| formats.is_empty())
.map(|(input_path, _)| PathBuf::from(input_path))
.collect();
if !files_missing_format.is_empty() {
let error = FinalError::with_title("Cannot decompress files without extensions")
.detail(format!(
"Files without supported extensions: {}",
concatenate_os_str_list(&files_missing_format)
))
.detail("Decompression formats are detected automatically by the file extension")
.hint("Provide a file with a supported extension:")
.hint(" ouch decompress example.tar.gz")
.hint("")
.hint("Or overwrite this option with the '--format' flag:")
.hint(format!(" ouch decompress {} --format tar.gz", to_utf(&files_missing_format[0])));
return Err(error.into());
}
// The directory that will contain the output files
// We default to the current directory if the user didn't specify an output directory with --dir
let output_dir = if let Some(dir) = output_dir {
if !utils::clear_path(&dir, question_policy)? {
// User doesn't want to overwrite
return Ok(());
}
utils::create_dir_if_non_existent(&dir)?;
dir
} else {
PathBuf::from(".")
};
for ((input_path, formats), file_name) in files.iter().zip(formats).zip(output_paths) {
let output_file_path = output_dir.join(file_name); // Path used by single file format archives
decompress_file(input_path, formats, &output_dir, output_file_path, question_policy)?;
}
}
Subcommand::List { archives: files, tree } => {
let mut formats = vec![];
for path in files.iter() {
let (_, file_formats) = extension::separate_known_extensions_from_name(path);
formats.push(file_formats);
}
if let ControlFlow::Break(_) = check_mime_type(&files, &mut formats, question_policy)? {
return Ok(());
}
let not_archives: Vec<PathBuf> = files
.iter()
.zip(&formats)
.filter(|(_, formats)| !formats.get(0).map(Extension::is_archive).unwrap_or(false))
.map(|(path, _)| path.clone())
.collect();
if !not_archives.is_empty() {
let error = FinalError::with_title("Cannot list archive contents")
.detail("Only archives can have their contents listed")
.detail(format!("Files are not archives: {}", concatenate_os_str_list(&not_archives)));
return Err(error.into());
}
let list_options = ListOptions { tree };
for (i, (archive_path, formats)) in files.iter().zip(formats).enumerate() {
if i > 0 {
println!();
}
let formats = formats.iter().flat_map(Extension::iter).map(Clone::clone).collect();
list_archive_contents(archive_path, formats, list_options)?;
}
}
}
Ok(())
}
// Compress files into an `output_file`
//
// files are the list of paths to be compressed: ["dir/file1.txt", "dir/file2.txt"]
// formats contains each format necessary for compression, example: [Tar, Gz] (in compression order)
// output_file is the resulting compressed file name, example: "compressed.tar.gz"
fn compress_files(files: Vec<PathBuf>, formats: Vec<Extension>, output_file: fs::File) -> crate::Result<()> {
// The next lines are for displaying the progress bar
// If the input files contain a directory, then the total size will be underestimated
let (total_input_size, precise) = files
.iter()
.map(|f| (f.metadata().expect("file exists").len(), f.is_file()))
.fold((0, true), |(total_size, and_precise), (size, precise)| (total_size + size, and_precise & precise));
//NOTE: canonicalize is here to avoid a weird bug:
// > If output_file_path is a nested path and it exists and the user overwrite it
// >> output_file_path.exists() will always return false (somehow)
// - canonicalize seems to fix this
let output_file_path = output_file.path().canonicalize()?;
let file_writer = BufWriter::with_capacity(BUFFER_CAPACITY, output_file);
let mut writer: Box<dyn Write> = Box::new(file_writer);
// Grab previous encoder and wrap it inside of a new one
let chain_writer_encoder = |format: &CompressionFormat, encoder: Box<dyn Write>| -> crate::Result<Box<dyn Write>> {
let encoder: Box<dyn Write> = match format {
Gzip => Box::new(flate2::write::GzEncoder::new(encoder, Default::default())),
Bzip => Box::new(bzip2::write::BzEncoder::new(encoder, Default::default())),
Lz4 => Box::new(lzzzz::lz4f::WriteCompressor::new(encoder, Default::default())?),
Lzma => Box::new(xz2::write::XzEncoder::new(encoder, 6)),
Zstd => {
let zstd_encoder = zstd::stream::write::Encoder::new(encoder, Default::default());
// Safety:
// Encoder::new() can only fail if `level` is invalid, but Default::default()
// is guaranteed to be valid
Box::new(zstd_encoder.unwrap().auto_finish())
}
Tar | Zip => unreachable!(),
};
Ok(encoder)
};
for format in formats.iter().flat_map(Extension::iter).skip(1).collect::<Vec<_>>().iter().rev() {
writer = chain_writer_encoder(format, writer)?;
}
match formats[0].compression_formats[0] {
Gzip | Bzip | Lz4 | Lzma | Zstd => {
let _progress = Progress::new_accessible_aware(
total_input_size,
precise,
Some(Box::new(move || output_file_path.metadata().expect("file exists").len())),
);
writer = chain_writer_encoder(&formats[0].compression_formats[0], writer)?;
let mut reader = fs::File::open(&files[0]).unwrap();
io::copy(&mut reader, &mut writer)?;
}
Tar => {
let mut progress = Progress::new_accessible_aware(
total_input_size,
precise,
Some(Box::new(move || output_file_path.metadata().expect("file exists").len())),
);
archive::tar::build_archive_from_paths(
&files,
&mut writer,
progress.as_mut().map(Progress::display_handle).unwrap_or(&mut io::stdout()),
)?;
writer.flush()?;
}
Zip => {
eprintln!("{yellow}Warning:{reset}", yellow = *colors::YELLOW, reset = *colors::RESET);
eprintln!("\tCompressing .zip entirely in memory.");
eprintln!("\tIf the file is too big, your PC might freeze!");
eprintln!(
"\tThis is a limitation for formats like '{}'.",
formats.iter().map(|format| format.to_string()).collect::<String>()
);
eprintln!("\tThe design of .zip makes it impossible to compress via stream.");
let mut vec_buffer = io::Cursor::new(vec![]);
let current_position_fn = {
let vec_buffer_ptr = {
struct FlyPtr(*const io::Cursor<Vec<u8>>);
unsafe impl Send for FlyPtr {}
FlyPtr(&vec_buffer as *const _)
};
Box::new(move || {
let vec_buffer_ptr = &vec_buffer_ptr;
// Safety: ptr is valid and vec_buffer is still alive
unsafe { &*vec_buffer_ptr.0 }.position()
})
};
let mut progress = Progress::new_accessible_aware(total_input_size, precise, Some(current_position_fn));
archive::zip::build_archive_from_paths(
&files,
&mut vec_buffer,
progress.as_mut().map(Progress::display_handle).unwrap_or(&mut io::stdout()),
)?;
let vec_buffer = vec_buffer.into_inner();
io::copy(&mut vec_buffer.as_slice(), &mut writer)?;
}
}
Ok(())
}
// Decompress a file
//
// File at input_file_path is opened for reading, example: "archive.tar.gz"
// formats contains each format necessary for decompression, example: [Gz, Tar] (in decompression order)
// output_dir it's where the file will be decompressed to, this function assumes that the directory exists
// output_file_path is only used when extracting single file formats, not archive formats like .tar or .zip
fn decompress_file(
input_file_path: &Path,
formats: Vec<Extension>,
output_dir: &Path,
output_file_path: PathBuf,
question_policy: QuestionPolicy,
) -> crate::Result<()> {
assert!(output_dir.exists());
let total_input_size = input_file_path.metadata().expect("file exists").len();
let reader = fs::File::open(&input_file_path)?;
// Zip archives are special, because they require io::Seek, so it requires it's logic separated
// from decoder chaining.
//
// This is the only case where we can read and unpack it directly, without having to do
// in-memory decompression/copying first.
//
// Any other Zip decompression done can take up the whole RAM and freeze ouch.
if formats.len() == 1 && *formats[0].compression_formats == [Zip] {
let zip_archive = zip::ZipArchive::new(reader)?;
let files = if let ControlFlow::Continue(files) = smart_unpack(
Box::new(move |output_dir| {
let mut progress = Progress::new_accessible_aware(total_input_size, true, None);
crate::archive::zip::unpack_archive(
zip_archive,
output_dir,
progress.as_mut().map(Progress::display_handle).unwrap_or(&mut io::stdout()),
)
}),
output_dir,
&output_file_path,
question_policy,
)? {
files
} else {
return Ok(());
};
// this is only printed once, so it doesn't result in much text. On the other hand,
// having a final status message is important especially in an accessibility context
// as screen readers may not read a commands exit code, making it hard to reason
// about whether the command succeeded without such a message
info!(
accessible,
"Successfully decompressed archive in {} ({} files).",
nice_directory_display(output_dir),
files.len()
);
return Ok(());
}
// Will be used in decoder chaining
let reader = BufReader::with_capacity(BUFFER_CAPACITY, reader);
let mut reader: Box<dyn Read> = Box::new(reader);
// Grab previous decoder and wrap it inside of a new one
let chain_reader_decoder = |format: &CompressionFormat, decoder: Box<dyn Read>| -> crate::Result<Box<dyn Read>> {
let decoder: Box<dyn Read> = match format {
Gzip => Box::new(flate2::read::GzDecoder::new(decoder)),
Bzip => Box::new(bzip2::read::BzDecoder::new(decoder)),
Lz4 => Box::new(lzzzz::lz4f::ReadDecompressor::new(decoder)?),
Lzma => Box::new(xz2::read::XzDecoder::new(decoder)),
Zstd => Box::new(zstd::stream::Decoder::new(decoder)?),
Tar | Zip => unreachable!(),
};
Ok(decoder)
};
for format in formats.iter().flat_map(Extension::iter).skip(1).collect::<Vec<_>>().iter().rev() {
reader = chain_reader_decoder(format, reader)?;
}
let files_unpacked;
match formats[0].compression_formats[0] {
Gzip | Bzip | Lz4 | Lzma | Zstd => {
reader = chain_reader_decoder(&formats[0].compression_formats[0], reader)?;
let writer = utils::create_or_ask_overwrite(&output_file_path, question_policy)?;
if writer.is_none() {
// Means that the user doesn't want to overwrite
return Ok(());
}
let mut writer = writer.unwrap();
let current_position_fn = Box::new({
let output_file_path = output_file_path.clone();
move || output_file_path.clone().metadata().expect("file exists").len()
});
let _progress = Progress::new_accessible_aware(total_input_size, true, Some(current_position_fn));
io::copy(&mut reader, &mut writer)?;
files_unpacked = vec![output_file_path];
}
Tar => {
files_unpacked = if let ControlFlow::Continue(files) = smart_unpack(
Box::new(move |output_dir| {
let mut progress = Progress::new_accessible_aware(total_input_size, true, None);
crate::archive::tar::unpack_archive(
reader,
output_dir,
progress.as_mut().map(Progress::display_handle).unwrap_or(&mut io::stdout()),
)
}),
output_dir,
&output_file_path,
question_policy,
)? {
files
} else {
return Ok(());
};
}
Zip => {
eprintln!("Compressing first into .zip.");
eprintln!("Warning: .zip archives with extra extensions have a downside.");
eprintln!(
"The only way is loading everything into the RAM while compressing, and then write everything down."
);
eprintln!("this means that by compressing .zip with extra compression formats, you can run out of RAM if the file is too large!");
let mut vec = vec![];
io::copy(&mut reader, &mut vec)?;
let zip_archive = zip::ZipArchive::new(io::Cursor::new(vec))?;
files_unpacked = if let ControlFlow::Continue(files) = smart_unpack(
Box::new(move |output_dir| {
let mut progress = Progress::new_accessible_aware(total_input_size, true, None);
crate::archive::zip::unpack_archive(
zip_archive,
output_dir,
progress.as_mut().map(Progress::display_handle).unwrap_or(&mut io::stdout()),
)
}),
output_dir,
&output_file_path,
question_policy,
)? {
files
} else {
return Ok(());
};
}
}
// this is only printed once, so it doesn't result in much text. On the other hand,
// having a final status message is important especially in an accessibility context
// as screen readers may not read a commands exit code, making it hard to reason
// about whether the command succeeded without such a message
info!(accessible, "Successfully decompressed archive in {}.", nice_directory_display(output_dir));
info!(accessible, "Files unpacked: {}", files_unpacked.len());
Ok(())
}
// File at input_file_path is opened for reading, example: "archive.tar.gz"
// formats contains each format necessary for decompression, example: [Gz, Tar] (in decompression order)
fn list_archive_contents(
archive_path: &Path,
formats: Vec<CompressionFormat>,
list_options: ListOptions,
) -> crate::Result<()> {
let reader = fs::File::open(&archive_path)?;
// Zip archives are special, because they require io::Seek, so it requires it's logic separated
// from decoder chaining.
//
// This is the only case where we can read and unpack it directly, without having to do
// in-memory decompression/copying first.
//
// Any other Zip decompression done can take up the whole RAM and freeze ouch.
if let [Zip] = *formats.as_slice() {
let zip_archive = zip::ZipArchive::new(reader)?;
let files = crate::archive::zip::list_archive(zip_archive)?;
list::list_files(archive_path, files, list_options);
return Ok(());
}
// Will be used in decoder chaining
let reader = BufReader::with_capacity(BUFFER_CAPACITY, reader);
let mut reader: Box<dyn Read> = Box::new(reader);
// Grab previous decoder and wrap it inside of a new one
let chain_reader_decoder = |format: &CompressionFormat, decoder: Box<dyn Read>| -> crate::Result<Box<dyn Read>> {
let decoder: Box<dyn Read> = match format {
Gzip => Box::new(flate2::read::GzDecoder::new(decoder)),
Bzip => Box::new(bzip2::read::BzDecoder::new(decoder)),
Lz4 => Box::new(lzzzz::lz4f::ReadDecompressor::new(decoder)?),
Lzma => Box::new(xz2::read::XzDecoder::new(decoder)),
Zstd => Box::new(zstd::stream::Decoder::new(decoder)?),
Tar | Zip => unreachable!(),
};
Ok(decoder)
};
for format in formats.iter().skip(1).rev() {
reader = chain_reader_decoder(format, reader)?;
}
let files = match formats[0] {
Tar => crate::archive::tar::list_archive(reader)?,
Zip => {
eprintln!("Listing files from zip archive.");
eprintln!("Warning: .zip archives with extra extensions have a downside.");
eprintln!("The only way is loading everything into the RAM while compressing, and then reading the archive contents.");
eprintln!("this means that by compressing .zip with extra compression formats, you can run out of RAM if the file is too large!");
let mut vec = vec![];
io::copy(&mut reader, &mut vec)?;
let zip_archive = zip::ZipArchive::new(io::Cursor::new(vec))?;
crate::archive::zip::list_archive(zip_archive)?
}
Gzip | Bzip | Lz4 | Lzma | Zstd => {
panic!("Not an archive! This should never happen, if it does, something is wrong with `CompressionFormat::is_archive()`. Please report this error!");
}
};
list::list_files(archive_path, files, list_options);
Ok(())
}
/// Unpacks an archive with some heuristics
/// - If the archive contains only one file, it will be extracted to the `output_dir`
/// - If the archive contains multiple files, it will be extracted to a subdirectory of the output_dir named after the archive (given by `output_file_path`)
/// Note: This functions assumes that `output_dir` exists
fn smart_unpack(
unpack_fn: Box<dyn FnOnce(&Path) -> crate::Result<Vec<PathBuf>>>,
output_dir: &Path,
output_file_path: &Path,
question_policy: QuestionPolicy,
) -> crate::Result<ControlFlow<(), Vec<PathBuf>>> {
assert!(output_dir.exists());
let temp_dir = tempfile::tempdir_in(output_dir)?;
let temp_dir_path = temp_dir.path();
info!(
accessible,
"Created temporary directory {} to hold decompressed elements.",
nice_directory_display(temp_dir_path)
);
// unpack the files
let files = unpack_fn(temp_dir_path)?;
let root_contains_only_one_element = fs::read_dir(&temp_dir_path)?.count() == 1;
if root_contains_only_one_element {
// Only one file in the root directory, so we can just move it to the output directory
let file = fs::read_dir(&temp_dir_path)?.next().expect("item exists")?;
let file_path = file.path();
let file_name =
file_path.file_name().expect("Should be safe because paths in archives should not end with '..'");
let correct_path = output_dir.join(file_name);
// One case to handle tough is we need to check if a file with the same name already exists
if !utils::clear_path(&correct_path, question_policy)? {
return Ok(ControlFlow::Break(()));
}
fs::rename(&file_path, &correct_path)?;
info!(
accessible,
"Successfully moved {} to {}.",
nice_directory_display(&file_path),
nice_directory_display(&correct_path)
);
} else {
// Multiple files in the root directory, so:
// Rename the temporary directory to the archive name, which is output_file_path
// One case to handle tough is we need to check if a file with the same name already exists
if !utils::clear_path(output_file_path, question_policy)? {
return Ok(ControlFlow::Break(()));
}
fs::rename(&temp_dir_path, &output_file_path)?;
info!(
accessible,
"Successfully moved {} to {}.",
nice_directory_display(&temp_dir_path),
nice_directory_display(&output_file_path)
);
}
Ok(ControlFlow::Continue(files))
}
fn check_mime_type(
files: &[PathBuf],
formats: &mut Vec<Vec<Extension>>,
question_policy: QuestionPolicy,
) -> crate::Result<ControlFlow<()>> {
for (path, format) in files.iter().zip(formats.iter_mut()) {
if format.is_empty() {
// File with no extension
// Try to detect it automatically and prompt the user about it
if let Some(detected_format) = try_infer_extension(path) {
// Infering the file extension can have unpredicted consequences (e.g. the user just
// mistyped, ...) which we should always inform the user about.
info!(accessible, "Detected file: `{}` extension as `{}`", path.display(), detected_format);
if user_wants_to_continue_decompressing(path, question_policy)? {
format.push(detected_format);
} else {
return Ok(ControlFlow::Break(()));
}
}
} else if let Some(detected_format) = try_infer_extension(path) {
// File ending with extension
// Try to detect the extension and warn the user if it differs from the written one
let outer_ext = format.iter().next_back().unwrap();
if outer_ext != &detected_format {
warning!(
"The file extension: `{}` differ from the detected extension: `{}`",
outer_ext,
detected_format
);
if !user_wants_to_continue_decompressing(path, question_policy)? {
return Ok(ControlFlow::Break(()));
}
}
} else {
// NOTE: If this actually produces no false positives, we can upgrade it in the future
// to a warning and ask the user if he wants to continue decompressing.
info!(accessible, "Could not detect the extension of `{}`", path.display());
}
}
Ok(ControlFlow::Continue(()))
}
fn clean_input_files_if_needed(files: &mut Vec<PathBuf>, output_path: &Path) {
let mut idx = 0;
while idx < files.len() {
if files[idx] == output_path {
warning!("The output file and the input file are the same: `{}`, skipping...", output_path.display());
files.remove(idx);
} else {
idx += 1;
}
}
}